The studies that have led to this invention were supported by the Grant Agreement No. CSJU-GAM-SAGE-2008-001 as part of the Seventh Framework Program of the European Union (RP7/2007-2013).
The invention relates to a seal as well as a method for producing a seal as described in detail below.
Seals, particularly in the form of honeycomb seals, find application, in particular, in so-called gap-support systems in compressor and turbine components of turbomachines. In this case, the seals have the task of keeping to a minimum a sealing gap between a rotating blade system and a housing as well as gaps between a stationary vane system and the rotating rotor hubs, and to thereby guarantee a stable operating performance of the turbomachine with high efficiency. Usually, the rotating components of the turbine comprise sealing fins, which run in against the seals in the known way. This type of honeycomb seal is disclosed by WO 2004/061340 A1. It is known to join honeycomb seals to the corresponding compressor or turbine components by means of mechanical fastening means, by means of brazing, welding, or laser welding. In addition, it is known from EP 1 573 239 B1 or EP 2 620 598 A2 to produce honeycomb seals by means of generative manufacturing methods or thermal spraying methods and/or to introduce them directly onto the compressor or turbine components.
As a disadvantage of the known seals produced by means of generative or additive methods, in particular honeycomb seals, is the circumstance, however, that they must be built up with a minimum wall thickness that is pre-defined by the method parameters. This minimum wall thickness, however, is thicker than the conventionally produced honeycomb seals made of sheet metal, which leads to a poorer run-in behavior. The latter is expressed, for example, by a higher thermal and mechanical stress of the sealing fins at rotors, sealing rings and rotating blades during run-ins of honeycomb seals produced generatively or additively.